Air Driven Projectile

ABSTRACT

A system for propelling an air-driven projectile from an air gun includes an air gun with an elongate bore and a source of compressed air in fluid communication with the elongate bore. A projectile is disposed within the bore of the air gun, the projectile having an outer diameter that is less than an inner diameter of the elongate bore.

RELATED APPLICATIONS

This application claims priority to U.S. Provisional Patent Application No. 62/272,893 filed on Dec. 30, 2015 and U.S. Provisional Patent Application No. 62/297,646 filed on Feb. 19, 2016, both entitled “Mounting Assembly for Arrow Head” and is a continuation-in-part of U.S. patent application Ser. No. 15/094,629 filed on Apr. 8, 2016 entitled “Air Driven Projectile” and is a continuation-in-part of U.S. patent application Ser. No. 14/751,895 filed on Jun. 26, 2015 entitled “Projectile” all of which are incorporated herein by reference in their entireties.

FIELD OF THE INVENTION

This invention relates generally to projectiles. Specifically, it relates to an improved projectile for use in an air gun or bow.

The present technology relates generally to an apparatus and method for propelling a projectile from an air gun or a bow. When an elongate projectile is propelled from a barrel of an air gun, it suffers from poor interaction with the shaft of the barrel and also suffers from problems associated with stability while in flight. It is desirable to have an improved device and associated methods that solve those and other related problems.

The present technology also relates generally to an apparatus and method of attaching and aligning a removable arrow head to the shaft of an arrow. It is long known in the art to provide mechanical means for mounting removable arrowheads to the end of an arrow. However, when arrows hit a solid or semi-solid surface, current systems result in impact forces acting along the longitudinal length of the arrow shaft resulting in failure of the shaft itself. It is therefore desirable to have an improved way of mounting an arrowhead to the end of an arrow that minimizes breakage of the shaft.

BRIEF DESCRIPTION OF THE FIGURES

To further clarify the above and other aspects of the present invention, a more particular description of the invention will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings. It is appreciated that these drawings depict only typical embodiments of the invention and are therefore not to be considered limiting of its scope. The drawings are not drawn to scale. The invention will be described and explained with additional specificity and detail through the use of the accompanying drawings in which:

FIG. 1 is a perspective view of a projectile in accordance with one aspect of the technology;

FIG. 2a is a perspective view of a stabilizer in accordance with one aspect of the technology;

FIG. 2b is a side view of the stabilizer of FIG. 2 a;

FIG. 2c is a top view of the stabilizer of FIG. 2 a;

FIG. 2d is a bottom view of the stabilizer of FIG. 2 a;

FIG. 3a is a perspective view of a butt in accordance with one aspect of the technology;

FIG. 3b is a side view of the butt shown in FIG. 3 a;

FIG. 3c is a top view of the butt shown in FIG. 3 a;

FIG. 4a is a perspective view of a tip in accordance with one aspect of the technology;

FIG. 4b is a side view of the tip shown in FIG. 4 a;

FIG. 4c is a top view of the tip shown in FIG. 4 a;

FIG. 5a is a perspective view of a butt in accordance with one aspect of the technology;

FIG. 5b is a side view of the butt shown in FIG. 5 a;

FIG. 5c is a top view of the butt shown in FIG. 5 a;

FIG. 6 is a perspective view of a butt with an O-ring in accordance with one aspect of the technology;

FIG. 7 is a side view of a butt or slug in accordance with one aspect of the technology;

FIG. 8 is a perspective view of a projective in accordance with one aspect of the technology;

FIG. 9a is a perspective view of a butt in accordance with one aspect of the technology;

FIG. 9b is a side view of the butt shown in FIG. 9 a;

FIG. 10 is a side view of a butt in accordance with one aspect of the technology;

FIG. 11 is a side view of an insert to be placed within a distal end of an arrow in accordance with one aspect of the technology;

FIG. 12 is a perspective view of an insert to be placed within a distal end of an arrow in accordance with one aspect of the technology;

FIG. 13 is a side view of an outsert to be placed about a distal end of an arrow in accordance with one aspect of the technology;

FIG. 14 is a perspective view of an outsert to be placed about a distal end of an arrow in accordance with one aspect of the technology; and

FIG. 15 is a cross sectional view of an insert and outsert assembled on an arrow shaft and disposed within the barrel of a firearm.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENT

The following detailed description of exemplary embodiments of the invention makes reference to the accompanying drawings, which form a part hereof and in which are shown, by way of illustration, exemplary embodiments in which the technology may be practiced. While these exemplary embodiments are described in sufficient detail to enable those skilled in the art to practice the invention, it should be understood that other embodiments may be realized and that various changes to the technology may be made without departing from the spirit and scope of the present invention. Thus, the following more detailed description of the embodiments of the present technology is not intended to limit the scope of the invention, as claimed, but is presented for purposes of illustration only and not limitation to describe the features and characteristics of the present technology, to set forth the best mode of operation of the technology, and to sufficiently enable one skilled in the art to practice the invention. Accordingly, the scope of the present invention is to be defined solely by the appended claims.

The following detailed description and exemplary embodiments of the invention will be best understood by reference to the accompanying drawings, wherein the elements and features of the invention are designated by numerals throughout.

The present technology in its various embodiments, some of which are depicted in the figures herein, can be broadly described as an improved projectile having a tip disposed about the end of a shaft and butt elements disposed about the rear end of the shaft. In one aspect, a stabilizer member is disposed apart from the butt element. However, in another aspect, the butt also comprises a stabilizer member. Broadly speaking, the technology resides in a shaft with a tip sized to be slightly larger than the diameter of a rifle bore so as to stop further downward movement of the elongate projectile shaft within the bore. A cylindrical butt is disposed about the rear end of the elongate projectile shaft having a front face that induces a predetermined amount of drag about the butt. A cylindrical stabilizer can be disposed forward of the butt and also has a front face that induces an amount of drag about the stabilizer. Advantageously, the enhanced drag about the front face of the butt/stabilizer functions to “center” the elongate projectile while in flight, increasing the ability of the elongate projectile to travel straight to its intended target. While an elongate air projectile for use in an air gun is specifically referenced herein, one of ordinary skill in the art will recognize that the technology can be used in connection with an arrow used in a traditional bow, compound bow, or other device that is capable of providing a force to the rear end of the projectile. The resulting projectile is more accurate over longer distances than traditional elongate projectiles (i.e., arrows and elongate projectiles) and is safer and quieter than conventional firearms. In addition, aspects of the projectile may be used as a stand-alone slug to be fired from an air-gun. For example, in one aspect of the technology, the butt may be used by itself as a bullet or slug in an air gun.

The projectile disclosed herein may be used in connection with an air gun. An air gun is any variety of projectile weapon that propels projectiles by means of compressed air or other gas, in contrast to firearms which use a propellant charge. Air guns are used for hunting, pest control, recreational shooting (commonly known as plinking), and competitive sports, such as the Olympic 10 m Air Rifle and 10 m Air Pistol events. In one aspect of the technology, the elongate projectile is used in connection with an air gun having a rifled bore. Rifling is the process of making helical grooves in the barrel of a gun or firearm, which imparts a spin to a projectile around its longitudinal axis. This spin serves to gyroscopically stabilize the projectile, improving its aerodynamic stability and accuracy. Rifling is often described by its twist rate, which indicates the distance the rifling takes to complete one full revolution, such as a one inch turn in ten inches (1:10 inches), or a 1 millimeter turn in 254 mm (1:254 mm). A shorter distance indicates a “faster” twist, meaning that for a given velocity the projectile will be rotating at a higher spin rate. The combination of length, weight and shape of a projectile determines the twist rate needed to stabilize it—barrels intended for short, large-diameter projectiles like spherical lead balls require a very low twist rate, such as 1 turn in 48 inches (122 cm). Barrels intended for long, small-diameter bullets, such as the ultra-low-drag, 80-grain 0.223 inch bullets (5.2 g, 5.56 mm), use twist rates of 1 turn in 8 inches (20 cm) or faster.

In some cases, rifling will have twist rates that increase down the length of the barrel, called a gain twist or progressive twist. Long projectiles, such as the elongate projectiles described herein, are thought to require high twist rates and are recommended to be fired from a smoothbore barrel. Aspects of the technology described herein cure that deficiency.

Projectile shafts, including arrows, have various sizes and fletchings or vanes of different designs. These vanes are for the purpose of better stabilization to start the arrow or elongate projectile shaft spinning. Spinning the arrow shaft is important for shaft stabilization for a number of reasons. The present technology introduces additional elements for shaft stabilization. When a standard arrow shaft is released from a bow, the arrow shaft bends around the bow staff. This is due to the arrow being forced from a standstill to full speed very quickly. This bending back and forth creates drag and decreases arrow speed. The presence of vanes and fletchings, while intended to assist in shaft spinning, also creates drag and decreases arrow speed. While shooting an arrow or an elongate projectile with fletchings or vanes in an environment with cross-winds, accuracy of the projectile is severely hampered. This is not to say that fletchings may not be used in the current invention. Rather, in certain aspects, fletchings are not used.

With specific reference now to the figures, FIGS. 1-6 disclose an elongate projectile 5 in accordance with one aspect of the technology. The elongate projectile 5 comprises a shaft 10 having a tip 20, a butt 30, and a stabilizer 50. In one aspect of the technology, the shaft 10 is made of a carbon fiber. However, it is understood that the shaft 10 may be constructed from aluminum, plastic, or any other material suitable for an elongate projectile. In accordance with one aspect of the technology, the tip 20 comprises a machined brass cylinder tapering in both the forward and rearward directions. The outer diameter of the tip 20 is sized larger than the inner diameter of the bore of a rifle. For example, if the bore of a rifle was 0.500 inches (i.e., 50 caliber), the maximum outer diameter of the tip 20 could be sized at 0.515 inches. In this manner, the tip 20 acts as a stop for insertion of the projectile 5 into the bore of the rifle. The front end 21 of the tip 20 is tapered in order to maximize aerodynamics and reduce drag created from wind resistance. The rear end 22 of the tip 20 is also tapered. The tapering of the rear end 22 of the tip 20 functions to help center the tip 20 within the bore as the shaft 10 rests in the bore. In another aspect of the technology, the rear end 22 of the tip 20 is not tapered. Rather, it comprises a substantially flat face and an annular protrusion (or a plurality of at least three individual protrusions) that is collinear with the center of the bore and is intended to seat within the bore of the rifle and center the projectile 5 within the bore of the rifle. The inner diameter of the tip 20 is substantially similar to the outer diameter of the shaft 10 and is secured to the distal end of the shaft 10. In one aspect of the invention, the inner diameter of the tip 20 is substantially similar to the outer diameter of the shaft 10 near a rear opening 23 of the tip 20.

The front opening 24 of the tip 20 has a diameter smaller than the shaft 10 to provide for a “seat” for the distal end of the shaft 10. In yet another aspect, the tip 20 comprises a plurality of three blades or points disposed about the exterior of the front end 21 of the tip 20. The front end 21 may be sized to fit within the bore of the rifle with the three blades or points acting to center the shaft 10 within the bore.

In one aspect of the technology, the tip 20 is removably secured to the shaft 10 so that a variety of different tips may be used on the same shaft 10. For example, the tip 20 may be replaced with a broad-head tip for hunting purposes, flat faced tips for target practice, or other tips used for other purposes. The tip 20 may be threaded onto the shaft 10, press-fit, or permanently secured by glue or some other method known in the art. In one aspect of the technology, the tip 20 is made of a dense, heavy material such as brass. The tip 20 is designed to be heavier than the remainder of the shaft 10, the stabilizer 50, and the butt 30. In this manner, the center of gravity of the elongate projectile 5 is balanced forward of the center 11 of the elongate projectile 5 which results in increased stabilization of the projectile 5 during travel through the air. While reference is made to a machined tip, it is understood that the tip 20 may be cast, molded or manufactured in a number of methods known in the art.

In one aspect of the technology, the butt 30 comprises a rigid cylinder having an annular groove (or channel) 31 disposed near the front end of the cylinder and circumscribing the cylinder. The semi-rigid cylinder has an outer diameter that is sized slightly smaller than the inner diameter of the bore of a rifle. In one aspect, the rear end of the butt 30 is tapered to assist in the placement of the projectile 5 into the bore of the rifle. The annular groove 31 is sized to receive one or more resilient O-rings 60 therein with the O-rings 60 circumscribing the annular groove 31. When placed within the annular groove 31, the outer diameter of the O-ring 60 is sized slightly larger than the inner diameter of the rifle bore. In this manner, the O-ring 60 acts to seal the rifle bore to enable pressurized air from an air rifle to deliver a propulsive force to the elongate projectile 5. The O-ring 60 also engages the riflings within the bore. As the elongate projectile 5 is propelled down the bore of the rifle, the riflings cause the elongate projectile 5 to rotate within the shaft 10. The spinning or rotation of the elongate projectile 5 within the bore increases the stabilization of the elongate projectile 5 while in flight. The lack of fletchings or vanes that are traditionally used to achieve spinning, results in a more stable flight path in any type of cross-wind. In other words, the flight path of arrows or elongate projectiles that have traditionally relied on fletchings or vanes to spin while in flight are negatively affected by a cross wind catching on the fletchings or vanes. The present technology eliminates that concern allowing the projectile 5 to fly straighter and longer distances.

With reference to FIGS. 5a through 6, in accordance with one aspect of the technology, the annular groove 31 is tapered such that a front end 38 of the annular groove 31 has a smaller diameter than a back end 39 of the annular groove 31. An O-ring 60 (or other shaped sealing member) is placed in the groove 31 and is sized to fit around the smaller diameter of the front end 38 of the annular groove 31. As the elongate projectile 5 is inserted into the bore of the rifle, the O-ring 60 a rides on the front end 38 of the annular groove 31, the inside of the bore creating friction so that the O-ring 60 a resists placement into the bore. When a force is provided on the rear end of the butt 30 to propel the elongate projectile 5 out of the rifle, the O-ring 60 b resists movement based on frictional engagement with the inside of the bore of the rifle. As the elongate projectile 5 is propelled forward, the O-ring 60 b rides on the back end 39 of the annular groove 31. Because the back end 39 of the annular groove 31 has a diameter that is larger than the front end 38 of the annular groove 31, the O-ring is stretched to match the diameter of the annular groove 31. In this manner, the outer diameter of the O-ring increases and creates increased frictional engagement with the inside of the bore. Advantageously, the increased frictional engagement increases the seal with the inside of the bore improving the efficiency of the air propulsion and improving the engagement with the riflings on the inside of the bore.

In accordance with one aspect of the technology, the O-ring is made of a resilient material such as rubber, nitrile, or polymeric materials. The butt 30 is made from an acetal resin such as Delrin® though it may be made from any suitable material, including, but without limitation, polymers, plastics, alloys and the like. The butt 30 may be molded, extruded, machined, or formed by any suitable method known in the art. The annular groove 31 is placed in the forward half of the cylindrical butt 30. The side surfaces 37 of the butt 30 act as a bearing surface to facilitate travel down the bore of the rifle as the elongate projectile 5.

In accordance with one aspect of the technology, the front face 34 of the butt 30 is substantially perpendicular to a longitudinal axis of the elongate projectile shaft 10. Drag (sometimes called air resistance or air friction) refers to the force acting opposite to the relative motion of any object moving with respect to a surrounding fluid. This can exist between two fluid layers (or surfaces) or a fluid and a solid surface. In the instant application, the interaction between the air and the elongate projectile 5 as the elongate projectile 5 moves in its flight path and the front face 34 of the butt 30 creates drag or frictional forces that act about the outer edge 35 of the front face 34 of the butt 30. While the drag has the negative effect of reducing the speed of the elongate projectile 5, the frictional forces are distributed evenly about the outer edge 35 of the front face 34 and act to stabilize the flight path of the elongate projectile 5.

In accordance with one aspect of the technology, the front face 34 of the butt 30 may be tapered. For example, the front face 34 may be linearly tapered outward at a forty-five degree angle. The tapering of the front face 34 decreases the drag on the butt 30 thereby increasing the speed of the elongate projectile 5, but decreasing the stabilization of the elongate projectile 5 while in flight. While a forty-five degree angle is specifically referenced, the angle of the taper may vary as suits a particular application, particularly with respect to the balancing between increased stability versus increased drag. For example, the front face 34 may vary from ninety degrees (not tapered) to twenty-five degrees (significantly tapered) with a preferred tapering of forty-five degrees. In another aspect, the front face 34 may taper outwardly in a non-linear fashion forming a curved outer surface. The front face 34 may also be linearly tapered inward (or non-linearly, i.e., concave) to increase the amount of drag on the elongate projectile 5 while in flight. The increase in drag increases the stability of the flight path of the elongate projectile 5 at the expense of reduced speed of the projectile 5. The rear end of the butt 30 has a slight taper to facilitate placement of the butt 30 within the bore of a rifle. The inner diameter of the butt 30 is sized to receive an end of the shaft 10 therein. The butt 30 is secured to the shaft 10 permanently (e.g., glued, fused, etc.) or can be removably secured to replace the butt 30 if it becomes worn over time or if the user wishes to use the elongate projectile 5 in a different application (e.g., as a nocked arrow). In accordance with one aspect, the butt 30 is formed from the same material as the shaft 10 and is integrally formed with the shaft 10 rather than being separately manufactured and later coupled to the shaft 10.

A stabilizer 50 is disposed along the shaft 10 of the elongate projectile 5. In one aspect of the technology, the stabilizer 50 is cylindrically shaped with an annular groove 51 disposed therein. The annular groove 51 functions similar to the groove 31 located within the butt 30. That is, it houses an O-ring intended to engage with the riflings of the bore of a rifle. The engagement of the O-rings with the riflings causes the shaft 10 to rotate or spin within the bore. The resulting spinning action increases the elongate projectile 5 stability during flight. Side surfaces 52 of the stabilizer 50 act as bearing surfaces to facilitate travel of the shaft 10 down the bore of the rifle and create the ultimate flight path of the elongate projectile 5. In one aspect of the technology, the stabilizer 50 is spaced a distance of at least five times the diameter of the bore from the butt 30. In other words, if the bore of a rifle intended to propel the elongate projectile 5 has an inner diameter of 0.50 inches, the distance between the front face 34 of the butt 30 and the rear face 53 of the stabilizer 50 is 2.5 inches. The stabilizer 50 may be placed a distance beyond five times the diameter of the bore away from the butt 30 depending on the size of the bore and the relative weight of the elongate projectile 5. For elongate projectiles 5 that are relatively heavy, with a tip 20 that is light (based on a desired use of the tip 20) the stabilizer 50 may be placed nearer the center 11 of the shaft 10 in an effort to balance the elongate projectile 5 to maximize projectile stability. In one aspect of the technology, the annular groove 51 is disposed in the front half of the stabilizer 50. However, in other aspects, the annular groove 51 is disposed in the middle of the stabilizer 50 or towards the rear end of the stabilizer 50.

As with the butt 30, the front face 54 of the stabilizer 50 is substantially perpendicular to a longitudinal axis of the shaft 10 of elongate projectile 5. Similar to the drag created on the front face 34 of the butt 30, as the elongate projectile 5 travels through the air, frictional forces from the air act equally about the outer edge 55 of the front face 54 creating a stabilizing force on the elongate projectile 5 in flight. In one aspect of the technology, the front face 54 may be tapered outward to reduce the drag about the front face 54. In another aspect, the front face 54 may be tapered inward or concave to increase the drag on the front face 54.

While specific reference is made herein to a cylindrical front face 54, it is understood that the front face 54 of the stabilizer 50 (as well as the front face 34 of the butt 30) may have designs placed thereon to optimize the ratio between drag and projectile speed. For example, the front face 54 may not be perfectly planar. Rather, it may have protrusions, indentations, or other designs associated therewith. In addition, other modifications may be made to optimize projectile spin as suits a particular application. For example, one or both of the tip 20 and the stabilizer 50 may be equipped with grooves disposed at an angle to the longitudinal axis of the elongate projectile 5 to induce spinning when the elongate projectile 5 is launched from a smooth bore barrel, cross-bow, or other apparatus that lacks riflings. In certain aspects of the technology, the butt 30 is configured to act as the stabilizer 50. This may be in addition to a stabilizer 50 disposed elsewhere about the shaft 10, and may include fletchings that act as conventional stabilizers. It may also include aspects without any additional stabilization means.

With reference now generally to FIGS. 1-6 and specifically to FIG. 7, a butt 100 is shown having a beveled front face 102 on a proximal end 101. An internal bore 104 is sized to receive the shaft of an arrow therein. The butt 100 comprises a closed distal end 105 forming an enclosure about the internal bore 104. An annular groove or channel 110 is disposed between the distal 105 and proximal 101 ends of the butt 100. Much like the butt of FIGS. 5a and 5b , for example, or the stabilizer shown in 4 a and 4 b, the butt 100 of FIG. 7 does not have an O-ring disposed in the annular groove 110 and may be used without an O-ring both as a stand-alone projectile or in connection with an arrow. In the instance where the butt 100 is used as a slug or bullet in an air gun, there is no internal bore 104. Rather, the butt 100 is substantially solid. Advantageously, when used as a slug in an air gun, the butt 100 engages the riflings in the bore of the air gun compelling the slug to have a spinning action.

In accordance with one aspect of the technology, the annular groove 110 comprises a tapered front section 111 and a tapered rear section 112. While a tapered front section 111 and rear section 112 are both shown, it is understood that the butt 110 could comprise a tapered front section 111 or a tapered rear section 112 or both as suits a particular purpose. In accordance with one aspect where an O-ring (or other resilient member) is disposed within the annular groove 110, when the projectile (either in connection with an arrow or as a stand-alone slug) is propagated from an air-rifle, the air pressure from the air-rifle used to propel the projectile out of the air gun drives the O-ring forward over the tapered front section 111. Because the tapered front section 111 has an increasing outer diameter, as the O-ring is driven forward over the tapered front section 111, the O-ring expands. As the O-ring expands its outer diameter is increased and it engages the side walls of the internal bore of the air rifle. As the O-ring engages the internal bore of the air rifle, frictional forces created by the engagement drive the O-ring towards a rear section of the annular groove 110. It is believed that the pressure gradient from the pressurized air acting on the O-ring decreases as the projectile travels down the bore of the air rifle. Accordingly, it is believed that during its initial movement down the bore of the air rifle, the O-ring is driven forward and, due to its expansion over the front tapered section 111, engages the internal bore of the air gun. However, as the pressure gradient decreases during the initial movement down the bore, the frictional forces acting on the O-ring, driving the O-ring backward will be greater than the air pressure driving O-ring forward. As that happens, the O-ring will be driven backward and return to its biased (or non-expanded) state within the non-tapered portion of the annular groove 110. In one aspect, a frictional force continues to act on the O-ring as the projectile travels down the bore of the air rifle causing the O-ring to continue to move backward and over the rear tapered section 112. While in its biased state, the O-ring engages the sidewall of the internal bore, however, in one aspect, the engagement is not enough to create satisfactory “spinning” of the projectile. As the O-ring is propelled or driven backward over the rear tapered section 112, it expands and engages the internal bore to a greater degree creating a greater seal or greater engagement resulting in increased “spinning” of the projectile. It is believed that the degree to which the O-ring is advanced over the front tapered section 111 and its movement rearward as the projectile travels down the bore of the air gun is a function primarily of the sizing of the O-ring with respect to the internal bore of the air gun and the diameter of the annular groove 110, and the amount of pressure acting on the projectile from pressurized air. The system seeks equilibrium between the air pressure driving the O-ring forward, the frictional forces resulting from engagement of the O-ring with the internal bore of the air gun, and the O-ring's tendency to return to its biased state in the non-tapered section of the annular groove 110. Advantageously, the present technology takes advantage of all three forces to optimize engagement of the O-ring with the riflings of the bore of the air gun.

While reference is made to a single O-ring on butt 100, it is understood that one or more O-rings (or other resilient members) may be disposed in a single annular groove 110. In one aspect, it is believed that as a first O-ring is driven backward over the rear tapered section 112, a second O-ring, abutted against the first O-ring, is also driven backward pushing the first O-ring further over the rear tapered section 112 resulting in an increased engagement against the internal bore of the air gun. The foregoing examples include use of the butt 100 on an arrow as shown in FIG. 1, for example, or as a stand-alone slug shot from an air gun as a bullet. Moreover, while the front and rear tapered sections 111, 112 are shown as having opposing 45 degree slopes, it is understood that any angle less than 90 degrees (i.e., perpendicular to longitudinal axis of butt 100) and greater than 0 degrees (i.e., parallel to longitudinal axis of butt 100) may be used as suits a particular design. Moreover, while the front and rear tapered sections 111, 112 are shown as having substantially equal slopes when comparing the absolute value of the slopes, it is understood that the front and rear tapered sections 111, 112, may have different slopes as suits a particular design need. For example, the slope of the front tapered section 111 may be greater than the slope of the rear tapered section 112 or vice versa. In addition, the lengths of the front and rear tapered sections 111, 112 may be substantially equivalent or one may be longer than the other as suits a particular design need.

With reference to FIG. 8, in accordance with one aspect of the technology, a projectile 305 is disclosed having shaft 310. The projectile 305 comprises a tip 320, a butt 330, and one or more stabilizers 350. In accordance with one aspect, the front face 334 of the butt 330 is substantially perpendicular to a longitudinal axis of the elongate projectile shaft 310. The interaction between the air and the elongate projectile 305 as the elongate projectile 305 moves in its flight path and the front face 334 of the butt 330 creates drag or frictional forces that act about the outer edge 335 of the front face 334 of the butt 330. While the drag has the negative effect of reducing the speed of the elongate projectile 305, the frictional forces are distributed evenly about the outer edge 335 of the front face 334 and act to stabilize the flight path of the elongate projectile 305. In accordance with one aspect of the technology, the front face 334 of the butt 330 may be tapered. For example, the front face 334 may be linearly tapered outward at a forty-five degree angle. The tapering of the front face 334 decreases the drag on the butt 330 thereby increasing the speed of the elongate projectile 305, but decreasing the stabilization of the elongate projectile 5 while in flight. While a forty-five degree angle is specifically referenced, the angle of the taper may vary as suits a particular application, particularly with respect to the balancing between increased stability versus increased drag. In another aspect, the front face 334 may taper outwardly in a non-linear fashion forming a curved outer surface. The front face 334 may also be linearly tapered inward (or non-linearly, i.e., concave) to increase the amount of drag on the elongate projectile 305 while in flight. The increase in drag increases the stability of the flight path of the elongate projectile 305 at the expense of reduced speed of the projectile 305. The rear end of the butt 330 has a slight taper to facilitate placement of the butt 330 within the bore of a rifle. The inner diameter of the butt 330 is sized to receive an end of the shaft 310 therein. The butt 330 is secured to the shaft 310 permanently (e.g., glued, fused, etc.) or can be removably secured to replace the butt 330 if it becomes worn over time or if the user wishes to use the elongate projectile 305 in a different application (e.g., as a nocked arrow). In accordance with one aspect, the butt 330 is formed from the same material as the shaft 310 and is integrally formed with the shaft 310 rather than being separately manufactured and later coupled to the shaft 310.

One or more stabilizers 350 are disposed along the shaft 310 of the elongate projectile 305. In one aspect of the technology, the stabilizer 350 is cylindrically shaped with an annular groove 351 disposed therein. The annular groove 351 functions similar to the groove 331 located within the butt 330. That is, it can house an O-ring intended to engage with the riflings of the bore of a rifle, though use of an O-ring in the stabilizer 351 is not always necessary. In one aspect of the technology, the engagement of the O-rings with the riflings causes the shaft 310 to rotate or spin within the bore. The resulting spinning action increases the elongate projectile 305 stability during flight. Side surfaces 352 of the stabilizer 350 act as bearing surfaces to facilitate travel of the shaft 310 down the bore of the rifle and create the ultimate flight path of the elongate projectile 305. In one aspect of the technology, a single stabilizer 350 is spaced a distance of at least five times the diameter of the bore from the butt 330. In other words, if the bore of a rifle intended to propel the elongate projectile 305 has an inner diameter of 0.50 inches, the distance between the front face 334 of the butt 330 and the rear face 353 of the stabilizer 350 is 2.5 inches. The stabilizer 350 may be placed a distance beyond five times the diameter of the bore away from the butt 330 depending on the size of the bore and the relative weight of the elongate projectile 305. For elongate projectiles 305 that are relatively heavy, with a tip 320 that is light (based on a desired use of the tip 320) the stabilizer 350 may be placed nearer the center 311 of the shaft 310 in an effort to balance the elongate projectile 305 to maximize projectile stability. In one aspect of the technology, the annular groove 351 is disposed in the front half of the stabilizer 350. However, in other aspects, the annular groove 351 is disposed in the middle of the stabilizer 350 or towards the rear end of the stabilizer 350. While a single stabilizer 350 is referenced, multiple stabilizers 350 may be used as needed to balance the shaft 310 in its flight path. The distribution of multiple stabilizers 350 about the shaft 310 of projectile 305 will depend on the overall weight of the projectile 305 and the weight of the tip 320. It will also be a function of the size of the projectile 305.

As with the butt 330, the front face 354 of the stabilizer 350 is substantially perpendicular to a longitudinal axis of the shaft 310 of elongate projectile 35. Similar to the drag created on the front face 334 of the butt 330, as the elongate projectile 305 travels through the air, frictional forces from the air act equally about the outer edge 355 of the front face 354 creating a stabilizing force on the elongate projectile 305 in flight. In one aspect of the technology, the front face 354 may be tapered outward to reduce the drag about the front face 354. In another aspect, the front face 354 may be tapered inward or concave to increase the drag on the front face 354.

With reference to FIGS. 9a through 10, in accordance with one aspect of the technology, the annular groove 331 is tapered such that a front end 338 of the annular groove 331 has a smaller diameter than a back end 339 of the annular groove 331. An O-ring 360 (or other shaped sealing member) is placed in the groove 331 and is sized to fit around the smaller diameter of the front end 338 of the annular groove 331. As the elongate projectile 305 is inserted into the bore of the rifle, the O-ring 360 a rides on the front end 338 of the annular groove 331, the inside of the bore creating friction so that the O-ring 360 a resists placement into the bore. When a force is provided on the rear end of the butt 330 to propel the elongate projectile 305 out of the rifle, the O-ring 360 b resists movement based on frictional engagement with the inside of the bore of the rifle. As the elongate projectile 305 is propelled forward, the O-ring 360 b rides on the back end 339 of the annular groove 331. Because the back end 339 of the annular groove 331 has a diameter that is larger than the front end 338 of the annular groove 331, the O-ring is stretched to match the diameter of the annular groove 331. In this manner, the outer diameter of the O-ring increases and creates increased frictional engagement with the inside of the bore. Advantageously, the increased frictional engagement increases the seal with the inside of the bore improving the efficiency of the air propulsion and improving the engagement with the riflings on the inside of the bore.

In accordance with one aspect of the technology, the butt 330 comprises a second annular groove 380 having a front end 381 that slopes downward to a back end 382. That is, the slope of the first annular groove 331 and the second annular groove 380 are in opposite directions. The second annular groove 380 comprises an O-ring 390 that also rides on groove and moves between the front end 381 and back end 382 of the butt 330 in positions 390 a and 390 b, respectively. However, the O-ring 390 serves a different function than O-ring 360. When the projectile 305 is propelled from the bore of a gun, the pressure from the discharge of the gun propels the projectile from the gun but also has a tendency to push the O-ring 360 forward which decreases its engagement with the inner sidewall of the bore of the gun. O-ring 390 is placed behind O-ring 360 and functions to minimize this effect by moving from a first position 390 b when the butt 330 is in a stationary position and inserted within the bore of the gun, to a second position 390 a, when a volume of pressurized air is released from the gun into the bore to propel the projectile 305 out of the gun. In this manner, the pressurized air that is propelling the projectile 305 also moves the O-ring 390 forward on annular groove 300. As it moves from the back end 382 to the front end 381 in increases in diameter and, if the pressure is sufficient, engages the internal sidewall of the bore of the gun. This improves the sealing and propulsive effect of the pressurized air and also, in the case of a rifled bore, rotates the projectile as it is advanced through the bore of the gun. The O-ring 390 is biased in its first position 390 b. Thus, when the pressure within the bore has decreased to a level that does not drive the O-ring 390 into its second position 390 a, the O-ring 390 will have a tendency to retreat to its first position 390 b both from the natural bias of the O-ring, and the friction encountered at the inner sidewall of the bore of the gun. This occurs in a balanced manner so that as the pressure decreases within the bore, the O-ring 390 will likewise move backwards at a similar rate taking into account the frictional forces acting on the O-ring 390 when it engages the sidewall of the bore. Advantageously, the O-ring 390 minimizes interference that the pressurized air from the gun may have on the O-ring's 360 ability to engage the sidewall of bore.

While the figures show that the opposing slopes have an identical slope, it is understood that the slopes of the respective grooves may be different. In one aspect one or either of the grooves may have no slope at all. In one aspect, the first and second grooves may have differing diameters to accommodate the different functions of the respective annular grooves. Likewise, the respective O-rings may be sized differently. That is, in one aspect, the diameter of the first groove 331 is larger than the diameter of the second groove 380. In another aspect, the diameter of the first groove is smaller than the diameter of the second groove 380. In one aspect, the slope of the first groove 331 is greater than the slope of the second groove 380 and vice versa. Moreover, the O-ring 360 may be larger (in diameter, thickness, etc.) than O-ring 390 and vice versa. In yet another aspect, the length of the first groove 331 is greater than the length of the second groove 380 and vice versa.

The present technology also describes systems, devices, and methods for mounting an arrowhead tip to the shaft of an arrow. Previous practices fall short of providing optimal mounting devices due, in part, to localized forces acting on the tip of the shaft resulting in failure of the shaft wall. Generally speaking, in one aspect of the technology, an insert and outsert are provided for placement about the distal end of an arrow shaft. Advantageously, placement of the insert and outsert about the distal end of the arrow shaft results in an increase in the strength of the distal end of the shaft and a distribution of forces about the longitudinal length of the shaft. In one aspect, the outsert holds the shaft of the arrow in compression increasing the hoop strength of the shaft.

With reference now to FIGS. 11-15, an insert 405 is shown. The insert 405 may be manufactured from any rigid material, including, but without limitation, aluminum, steel, or other metal or metal alloy, polyurethane, or other rigid synthetic material. The insert 405 may be molded, extruded, machined, or manufactured in accordance with other known methods. The insert 405 comprises a proximal cylindrical shaft 410 that is sized to approximate the inner diameter 431 of an arrow shaft 430. A cylindrical head 411 is disposed about the distal end of the cylindrical shaft 410. An outer diameter 412 of the head 411 is sized to approximate the outer diameter 432 of the arrow shaft 430. In this manner, once the insert 405 is disposed within the shaft of the arrow 430, the external surface 434 of the arrow shaft 430 will be substantially coplanar with the external surface of the cylindrical head 411. The cylindrical head 411 and shaft 410 comprise an aperture 413 that extends through the head 411 and at least partially through the cylindrical shaft 410. The aperture 413 is sized to receive the distal end of an arrowhead therein. In one aspect, the aperture 413 is threaded in order to accommodate a threaded end of an arrowhead.

In accordance with one aspect of the technology, an outsert 415 is provided in the general shape of a trapezoid. The outsert 415 also comprises a rigid material, including, but without limitation, aluminum, steel, or other metal or metal alloy, polyurethane, or other rigid synthetic material and may be molded, extruded, machined, or manufactured in accordance with other known methods. The outsert 415 comprises a head 416 having an outer diameter 417 tapering to a tail 418 having a diameter smaller than the diameter of the head 416. The head 416 is beveled to accommodate placement of an arrowhead thereon. A lumen 425 extends through the outsert 415 and is sized to receive the shaft of an arrowhead therein, the shaft passing through the lumen 425 and being received into the aperture 413 disposed within the insert 405. The lumen 425 within the outsert 415 is divided into two sections each having a different inner diameter. A first inner diameter 419 is located about the distal end or tail 418 of the outsert 415. The inner diameter 419 located near the distal end or tail 418 of the outsert 415 is sized to approximate the outer diameter of the arrow shaft and outer diameter of the cylindrical head 411 on the insert 405. The second diameter 420 is located near the proximal end or head of the outsert and is smaller than the first diameter 419. The second diameter 420 is sized to receive a portion of the shaft of an arrowhead therein. In one aspect, the first diameter 419 and second diameter 420 each occupy about half of the length of the outsert 415. However, those lengths may be modified as suits a particular purpose. For example, the length of the first diameter 418 may be up to ¾ of the total length of the outsert 415 or it may be as little as ¼ of the total length of the outsert 415.

With reference to FIG. 15, an insert 405 is shown glued, bonded or otherwise coupled to an internal surface of an arrow shaft 430. The arrow shaft 430 may be made of a carbon fiber or other material as is known in the art. The outsert 415 is placed over an outer surface of the head 411 of the insert 405 and the outer surface of arrow shaft 430. In accordance with one aspect of the technology, the head 411 of the insert 405 is located near a midpoint of the outsert 415. As such, the tail 418 of the outsert 415 extends over the distal end of the arrow shaft 430 about half the length of the outsert 415. In one non-limiting example, the outsert 415 is 1 inch long having a lumen 425 with a first inner diameter 419 that extends approximately 0.55 inches within the tail 418 of the outsert 415 and a second inner diameter 420 that extends about 0.45 inches within the head 416 of the insert 415. In one aspect, the insert 405 extends into the distal end of the arrow shaft 430 approximately 1 inch with the outsert 415 extending over an outer portion of the shaft 430 less than the length of the insert 405 within the arrow shaft. However, in another aspect, the outsert 415 extends over an outer portion of the arrow shaft 430 approximately the same distance as the insert 405 extends within the shaft. In another example, the outsert 415 extends over the outer portion of the arrow shaft 430 more than the insert 405 extends within the shaft 430. In any event, the outsert 415 extends over the outside of the arrow shaft 430 at least as much as the aperture 413 within the insert 405 extends into the arrow shaft 430. When the outsert 415 and insert 405 are coupled together, the insert 405 maintains the face of the outsert 415 in a position that is perpendicular to the shaft of the arrow. It also maintains the lumen 425 of the outsert 415 concentric with the shaft of the arrow.

In accordance with one aspect of the technology, the distal end of the insert 405 comprises a plurality of grooves or apertures. The grooves or apertures are intended to create additional space (i.e., a bonding area) for a bonding agent to adhere to an outer surface of the insert 405 and an inner surface of the arrow shaft 430. Without grooves or apertures, the insert 405 may be lengthened further to increase the bonding area available for the technology.

In another aspect of the technology, the outsert 415 is configured to act as a guide for centering the arrow within the barrel 440 of a firearm. The outer diameter of the outsert 415 at the largest diameter of the head 416 is sized larger than the internal diameter 441 of the barrel 440 of the firearm. Placed within the end of the barrel 440 of the firearm, the head 416 of the outsert 415 centers the outsert 415 within the barrel 440. While FIG. 15 discloses wherein the shape of the head 416 is circular, other shapes of the head 416 are considered for use herein. In one non-limiting example, the head 416 of the outsert 415 is a quadrilateral having four touch points that contact the face of the barrel 440 of the firearm. Those touch points center the lumen 425 of the outsert within the barrel of the firearm. The head 416 may have five, six, seven, eight, or many touch points as suits a particular design so long as a minimum of three touch points are present.

While the foregoing examples are illustrative of the principles of the present invention in one or more particular applications, it will be apparent to those of ordinary skill in the art that numerous modifications in form, usage and details of implementation can be made without the exercise of inventive faculty, and without departing from the principles and concepts of the invention. Moreover, one or more aspects of the technology may be combined together or removed without departing from the scope of the invention and principles of operation disclosed herein. Accordingly, it is not intended that the invention be limited, except as by the claims set forth below. 

1. A projectile, comprising: an elongate tubular member; a tip disposed about a distal end of the elongate tubular member; a butt disposed about a proximal end of the elongate tubular member, wherein the butt has an outer diameter that is greater than an outer diameter of the elongate tubular member and comprises a rear face having a diameter greater than the diameter of the elongate tubular member; first and second annular grooves disposed about the butt, said annular grooves circumscribing the butt and each comprising an O-ring.
 2. The projectile of claim 1, wherein the annular grooves each comprises a tapered section having a slope, wherein the slopes of each of the tapered sections are in opposite directions.
 3. The projectile of claim 2, wherein the slope of the tapered groove of the first section is equivalent to the slope of the tapered groove of the second section.
 4. The projectile of claim 2, wherein the slope of the tapered groove of the first section is less than the slope of the tapered groove of the second section.
 5. The projectile of claim 2, wherein the slope of the tapered groove of the first section is greater than the slope of the tapered groove of the second section.
 6. The projectile of claim 2, wherein a diameter of the first groove is less than a diameter of the second groove.
 7. The projectile of claim 2, wherein a diameter of the first groove is greater than a diameter of the second groove.
 8. The projectile of claim 2, wherein a diameter of the O-ring of the first groove in an unbiased state is less than a diameter of the O-ring of the second groove in an unbiased state.
 9. The projectile of claim 2, wherein a diameter of the O-ring of the first groove in an unbiased state is greater than a diameter of the O-ring of the second groove in an unbiased state.
 10. The projectile of claim 2, wherein a length of the first groove is greater than or less than a length of the second groove.
 11. The projectile of claim 2, further comprising a plurality of cylindrical stabilizers disposed about the elongate tubular member, each stabilizer comprising a tapered face.
 12. A method of propelling a projectile from an air gun, comprising: placing a quantity of pressurized fluid into the air gun, the quantity of pressurized fluid in fluid communication with a bore of the air gun; placing an elongate projectile into the bore of the air gun, wherein said elongate projectile comprises a cylindrical butt disposed about a proximal end of the elongate projectile, the butt having a first and second annular grooves; releasing the pressurized fluid into the bore of the air gun propelling the elongate projectile from the bore of the air gun, wherein as the elongate projectile is propelled down the bore of the air gun, the O-ring frictionally advances over the tapered section and engages riflings within the air gun causing the elongate projectile to rotate within the bore of the air gun.
 13. The method of claim 12, wherein each of the annular grooves comprise a tapered section.
 14. The method of claim 12, wherein an O-ring is disposed in each of the annular grooves.
 15. The method of claim 14, wherein when the projectile is propelled out of the bore of the air gun, the O-ring in the first groove is forced to the rear of the first groove and the O-ring in the second groove is forced to the front of the second groove.
 16. A mounting system for an arrow, comprising: a substantially cylindrical member having an aperture on a distal end sized to receive an arrowhead therein; and a conical member disposed about an exterior of the substantially cylindrical member, the conical member having a through lumen that is in fluid communication with the aperture of the substantially cylindrical member.
 17. The mounting system of claim 16, further comprising an arrow having the substantially cylindrical member disposed in a distal end and the conical member disposed about an exterior of the cylindrical member and the distal end of the arrow.
 18. The mounting system of claim 16, wherein a head of the conical member is tapered.
 19. The mounting system of claim 17, wherein a head of the conical member is sized to be greater than an internal diameter of a bore of a gun.
 20. The mounting system of claim 16, wherein the cylindrical member comprises a head and a tail, the tail having an outer diameter that is substantially equivalent to an inner diameter of an arrow and the head having an outer diameter that is substantially equivalent to an outer diameter of the arrow. 